Improvement in hand-pieces for dental engines



T. STARR.

HAND-PIECES Fonl DENTAL-ENGINES.

N.184.,99Z. Patented nec.5.1a7e.

WITNESSES v INVENTOR Eli-Tsja# W Y By y* Attwneys.

M @AMW WQ@ Tm: annul comm UNITED STATES PATENT DFFICE.

ELI T. STARR, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO SAMUEL S. WHITE, OF SAME PLAGE.

IMPROVEMENT IN HAND-P-IECES FOR DENTAL ENGINES.

Specification forming part of Letters Patent No. 184,992, dated December 5,1876; application filed October 24, 1876.

To all whom it may concern:

Be it known that I, ELI T. STARR, of the city and county of Philadelphia and State of Pennsylvania, haveinvented a new and useful Improvement in Hand-Piece Attachments for Dental Engines, of which the following is a specification:

The object of my invention is to enable the operator readily to stop or start the tool mounted in the hand-piece attachment witbout removing his lingers from the instrument, and witllout stopping the rotation of the drivin g-shaft ofthe engine, which end I attain by means of a novel organization of parts, hereinafter distinctly specified.

In the accompanying drawings, Figure l represents a vertical longitudinal section through my improved attachment, on the line 1 1 of Fig. 2; Fig'. 2, a transverse ksection on the line 2 2 ofFig. l; and Fig. 3, a-longitudinal section, on an enlarged scale, through the line3 3 of Fig. 2.

In this instrument myimprovernent is shown as adapted to an angle attachment of a dental engine, but obviously maybe employed in other well-known forms of attachments. The casing or barrel A of the attachment is shown as adapted for the reception of the nose or hand piece of the ordinary dental engine. A coupling-shaft, B, mounted axiallyin the bore of the casing, in suitable bearings, is provided at one end with a attened side and a trans- 'verse groove, to adapt it to the hand-piece of a clutch-coupling, D, sliding freely endwise on the shaft O, but prevented from turning by the usual longitudinal groove and feather, as clearly shown in the drawings. A spiral spring, C', encircling the shaft C, tends to hold the clutch locked with the coupling shaft. The shaft is disconnected, when desired, by means ot' the sliding ring E, movable endwise on the barrel A, and carrying a pin, e, projecting through a slot in the casing, into an annular groove, e', on the clutch, as usual.

In the drawings the driven shaft is shown as carrying a bevel-gear drivin g an angle-shaft adapted for the reception of adisk or burr; but in some instances I propose to substitute a straight nose for the bent angle-piece shown, to prolong the coupling-shaft, to dispense with the gearing, and to secure the tool or toolholder directly to the end of the shaft.

I claim as of my own invention- The hand-piece attachment for dental-engines hereinbefore described, consisting of the combination of the barrel or casing adapted to tit the hand-piece of a dental engine, the coupling-shaft mounted in said attachment and adapted to connect with the driving-shaft of the hand-piece, the driven shaft mounted in the attachment independent of the couplingshaft, the clutch-coupling connecting the two, and the sliding ring on the casing, whereby the operator is enabled to stop or start the tool without stopping the engine or couplingshaft.

In testimony whereof I have hereunto subscribed my name.

ELI T. STARR.

Witnesses: f

J. APB. WILLIAMS, ELI S. MUsTIN. 

